Illuminating means for indicating instruments



Oct. 11, 1938.

W. A. REICHEL ILLUMINATING MEANS FOR INDICATING INSTRUMENTS Filed Sept. 24, 1937 e 0 w e n A m m W Patented Oct. 11, 1938 UNITED s'rATas Y 8 I I 2,132.57: I I mnumarma MEANS ron mmcarmo I Wladimir a. magmatic, a. a, mm a.

Bendix Aviation Corporation, South-Bend, Ind;

aeorporation of Delaware The present invention relates to illuminating means and more particularly to. illuminating means for indicating instruments.

One oi the objects of the invention is to pro- 5 vide a novel structure comprising a readily removable and easily replaceable miniature electric lamp in combination with a cooperating socket especially adapted for use with an indicating instrument and positionable in the instru- 10 ment case to cooperate with aring-like lightconducting and light-emitting member for providing illumination of the indicating means of the instrument in the manner disclosed in the copending application 01 Gregory V. Rylsky, Serial No. 29,323. It is to be understood, however, that the lamp and socket structure of the present invention is not limited to the use thereof with the specific type of illumination disclosed in said copending application of Gregory V.- Rylsky but.

may be used in other combinations..

Heretoiore, miniature electric lamp and socket structures have been provided including a lampreceiving socket and a lamp comprising a miniature bulb having a filament therein and conducting leads extendingtherefrom, a base formed by a conductive sleeve member around the bulb and connected to one of the leads thereof, a second metallic member oi. annular form having a con-- nection to the other lead, and an insulating member separating the sleeve member and the second annular contact member. In assembling such prior art lamp structures during the manuiacture thereof, difllculty was encountered in placing the bulb into the conductive sleeve memher and in centering the bulb therein and in the base member inasmuch as the miniature lamp bulbs are not exactly cylindrical and hence are not always uniform. Accordingly, another object of the present invention is to provide a novel lamp structure wherein the foregoing manufacturing difllculties are eliminated and the several elements comprising the lamp are easily assembled and the bulb is accurately centered in its base.

Another object is to provide a novel miniature lamp structure comprising a plug base member having a finger-operable gripper portion and providing external electrical contacting metallic screw threads, an elongated miniature lamp bulb having terminal leads, a plurality of metallic prongs extending longitudinally of the lamp and adapted to grip the same and having their ends bent outwardly from the lamp to form contacts which are adapted to engage cooperating contact g5 means of a socket when the lamp structure is inserted therein, an insulating collar surrounding said prongs and abutting the outwardly bent portions thereof, said collar holding the prongs" and lamp in assembled relation and this assemblage being seated in the plug base member in 5 concentric relation therewith, connections for the terminal leads of the lamp tothe metallic screw threads and to the metallic prongs, and insulating plastic material in said plug base member for securing said lamp assembly in said base. 10 I Still another object is to provide a novel lamp and socket structure including, in combination, a lamp, a base for said lamp, and a socket for receiving the base and lamp, said lamp comprising an elongated closed miniature bulb having a 15 filament therein and conducting leads for the filament extending therefrom, said base comprising an annular memberhaving a lamp seat and external'metallic screw threads providing a first contact means electrically connected to one 20 of said conducting leads, a second contact means connected to the other of said conducting leads and comprising a plurality of metallic prongs extending longitudinally of the bulb and circumfelentially spaced therearound and having their 25 outer ends bent outwardly from the bulb, an insulating'collar surrounding said prongs and abutting the outwardly bent portions thereof, said collar holding the prongs and lamp in assembled relation and this assemblage being seated in the 30 lamp seat of the base member, and insulating plastic material in said base member for securing said lamp assembly therein, said socket comprising an insulating external portion, an internally threaded contact means in said insulating 35 portion and cooperating with the external threads 01' the base member, and a second contact means insulated from the internally threaded contact means and adapted to contact with the outwardly bent portions of the prongs oi. the lamp 0 assembly when said lamp is inserted into said socket.

A still further object of the invention is to provide a novel miniature lamp structure which is relatively simple and easily assembled in the 45 process of manufacture whereby such lamps'inay be made inexpensively in large quantities.

The above and other objects and advantages of the invention will appear more fully hereinafter from a consideration oi. the detailed description 50 which follows, taken together with the accompanying drawing wherein one embodiment of the invention is illustrated. It is to be expressly understood, however, that the drawing is for the. purpose or illustration and description only and is not to be construed as defining the limits of the invention, reference being had for this purpose to the appended claims.

In the drawing wherein like reference characters refer to like parts throughout the several views,

Fig. 1 is an exploded view, in perspective, of

-one form of lamp structure embodying the present invention, certain parts being in section, showing the relation of the parts to each other and the manner in which they are to be assembled to form a unit;

Fig. 2 is a perspective view similar to Fig. 1, showing the parts partially assembled;

Fig. 3 is a longitudinal section of the lamp structure completely assembled;

Fig. 4 is an end view of the lamp structure as seen from the bottom of Fig. 3; and

Fig. 5 is a sectional view of both the lamp and the socket structure, showing the lamp about to be inserted into the socket which is located in the casing of an instrument to be illuminated, only a portion of the casing being shown.

In its broad aspects, the invention consists substantially in the construction, combination, location and relative arrangement of parts for obtaining the results in accordance with the foregoing objects, as will be more fully hereinafter set forth in the specification, as shown in the drawing by way of example, and as finally pointed out in the claims. 7

Referring to the drawing and more particularly to Fig. l, the novel lamp structure of the invention comprises in the present instance, as shown, an annular metallic base 6 having a fingeroperable knurled gripper portion 1 and an externally screw-threaded portion 8 which forms one of the contact means for connecting one end of the filament of the lamp thereto as will appear more fully hereinafter. The base is hollowed out to form a lamp seat 9 and is provided with a central aperture l extending from the lamp seat to the exterior of said base.

Adapted to be inserted into and seated in the lamp seat 9 of said base 6 is an insulating sleeve or collar ll having an annular flange l2 at its outer projecting end. said flange being adapted, when in place in the seat 9, to abut the end of the externally threaded portion 8 of said base 6.

The collar II is provided on the inside thereof with a plurality of longitudinal grooves or slots I3 circumferentially spaced for respectively receiving and securing therein each of a plurality of metallic prongs or fingers H which are formed integrally with a bridging piece l and which have their ends bent outwardly as indicated at l6. These fingers or prongs form the second contact means for connecting the other end of the filament of the lamp thereto.

Before assembly, the prongs or fingers H, which are resilient in the present instance, are arranged in outwardly sprung relation, as shown in Fig. 1, to receive the lamp bulb ll. Upon insertion of the lamp bulb ll between the fingers or prongs M, the insulating sleeve or collar H is slipped over said fingers or prongs so that the latter slide into their respective grooves or slots I 3 and project, together withtheir bridging piece l5, beyond the inner end of the sleeve or collar H, with the outwardly bent portions l6 abutting the flange l2 of said collar or sleeve as shown in Fig. 2. In the present embodiment there are shown three such fingers or prongs l4 and there are correspondingly provided three grooves or slots I3 on the inside of the collar or sleeve II. It is apparent, however, that there may be less than three or more than three such fingers or prongs and a corresponding number of slots or grooves as desired.

The lamp bulb H has a filament 18 therein supported in the usual manner well known to those skilled in the lamp art, with conducting leads I9 and 20 leading from said filament l8 and passing through the material of said lamp bulb as shown in Figs. 1 and 2.

Before the sleeve or collar II is slipped over the fingers or prongs [4, the conducting lead i9 is soldered or otherwise connected to the bridging piece l5 as shown in Fig. 2, and the conducting lead 20 is passed through a central opening 2| provided in the bridging piece l5 and is insulated from said piece and the fingers or prongs by an insulating sleeve 22 .as shown in Figs. 2 and 3. Then the sleeve or collar II is slipped over the prongs and the lamp bulb.

The assemblage thus far described is now ready for final assembly by insertion into the lamp seat 9 of the base 5 as indicated in Fig. 2, and for this purpose, the bare end of the lead 20 is first inserted into the central aperture H] of the base 6 and is soldered to said base by dropping a drop of solder 23 into said opening Hi to form an electrical connection, then the space forming the lamp seat 9 is partially filled with plastic adhesive insulating material 24, and finally the sub-assembly comprising the lamp l1, sleeve or collar II and fingers or prongs i4 is inserted into the lamp seat 9, whereby this sub-assembly is embedded in the plastic material 24 and securely held in said base 6 upon hardening of said plastic insulating material. 7

There is now provided a novel lamp socket structure for receiving the above-described lamp structure and in Fig. 5 such a socket structure is shown as forming part of an indicating instrument the indicating means of which is to be illuminated in the manner disclosed and described in the aforementioned co-pending application of Gregory V. Rylsky. Serial No. 29,323.

As illustrated, the socket structure comprises a molded extension 24a formed integrally with the casing 25 of which only the necessary portion is shown. The molded extension 24a, however, may be part of an adapter or frame which is arranged to be secured to a previously constructed instrument, in the manner disclosed, in another copending application of said Gregory V. Rylsky, Serial No. 141,525.

Within the molded extension 24a, which is of insulating material, there is provided an internally threaded metallic sleeve member 26 which is adapted to receive and engage the externally threaded portion 8 of the base 6 of the lamp structure when the latter is inserted into the socket. Arranged concentrically with the molded extension 2411 and the internally threaded sleeve member 26 there is a boss 21 which is molded integrally with the casing 25 and is also of insulating material.

On the boss 21 is seated an annular contact member 28 comprising one or more turns of a coiled compression spring of conducting material whereby, upon insertion of the lamp into the socket, the outwardly bent portions l6 of the fingers or prongs I4 of the lamp structure engage said contact member 28 and compress the latter somewhat, thereby insuring positive electrical contact between the contact means l6 and 28.

Means are provided for connecting the internally threaded sleeve member 26 and the contact spring 28 to a source of electrical energy such as a battery (not shown). In the illustrated embodiment, said connecting means comprise leads 29 and 30, the lead 30 being directly soldered to the sleeve member 26 as indicated at 3|, and the lead 29 being connected to the spring contact 28 by a conducting rod 32 to which the lead 29 is soldered as shown at 33.

When the lamp is inserted into the socket, it takes the position Ila shown in dotted lines in Fig. 5 so as to extend between the ends of a glass ring 34, only one end 35, of said ring being shown, in the manner disclosed in the aforesaid application of Gregory V. Rylsky, Serial No. 29,323. The glass ring 34 conducts the olight from the lamp in a circular path adjacent the dial 36 and then emits the light onto said dial which is located behind the instrument cover glass 31, the latter being held in place by a snap ring 38.

There is thus provided a novel miniature lamp structure which is extremely simple, readily removable from a cooperating socket, easy to assemble in the process of manufacture, and particularly adapted for use with a lamp socket formed in an instrument casing for illuminating the indicating means of the instrument.

While only one embodiment of the invention has been illustrated and described, various changes in the form, construction and relative arrangement of the parts of the lamp structure, which will now appear to those skilled in the art, may be made without departing from the spirit or scope of the invention. Reference is, therefore, to be had to the appended claims for a definition of the limits 0! the invention.

What is claimed is:

1. A miniature lamp structure comprising a plug base member having a finger-operable grip-- per portion and providingexternal electrical contacting metallic screw threads, an elongated miniature lamp bulb having terminal leads, a plurality of metallic prongs extending longitudinally of the lamp and adapted to grip the same and having their ends bent outwardly from the lamptotormoontactswhichareadaptedto engage cooperating contact means of a socket when the lamp structure is inserted therein, an insulating collar surrounding said prongs and. abutting the outwardly bent portions thereof,

said collar holding the prongs and lamp in assembled relation and this assemblage being seated in the plug base member in concentric relation therewith, connections for the terminal leads of the lamp to the metallic screw threads and to the metallic prongs, and insulating plastic material in said plug base member for securing said lamp assembly in said base.

2. A miniature lamp and socket structure including, in combination, a lamp, 9. base for said lamp, and a socket for receiving the base and lamp, said lamp comprising an elongated closed miniature bulb having a filament therein and conducting leads for the filament extending therefrom, said base comprising an annular member having a lamp seat and external metallic screw threads providing a first contact means electrically connected to one of said conducting leads, a second contact means connected to the other of said conducting leads and comprising a plurality of metallic prongs extending longitudinally of the bulb and circumferentially spaced therearound and having their outer ends bent outwardly from the bulb, an insulating collar surrounding said prongs and abutting the outwardly bent portions thereof, said collar holding the prongs and lamp in assembled relation and i this assemblage being seated in the lamp seat of the base member, and insulating plastic material in said base member for securing said lamp assembly therein, said socket comprising an insulating external portion, an internally threaded contact means in said insulating portion and co operating with the external threads of the base.

member, and a second contact means insulated from the internally threaded contact means and adapted to contact with the outwardly bent portions of the prongs of the lamp assembly when said lamp is inserted into said socket.

WLADIMIR A. REICHEL. 

